1. Field of the Invention
The invention relates generally to materials useful as components of electronic devices such as transistors.
2. Description of the Prior Art
Because of their unique structural, mechanical and electrical properties, materials containing single-wall carbon nanotubes (SWCNTs) have been developed for electronic and sensor applications. However, two major obstacles have stood in the way of commercial electronic applications. The first obstacle is lack of position and orientation control. Such control is necessary for high-yield device fabrication. The second problem is lack of control of the precise atomic structure of SWCNTs. SWCNTs are currently produced with a range of diameters and different chiralities. These variations in atomic structure result in a wide variety of electronic properties ranging from semiconducting to metallic behavior. There has been little progress in solving either of these two problems that currently prohibit high yield device fabrication.
One electronic property of SWCNTs is the high room temperature mobility of semiconducting SWCNTs (s-SWCNTs) that is more than an order of magnitude larger than the mobility of crystalline Si. This high mobility has prompted fabrication and study of field-effect transistors in which a single s-SWCNT serves as a high-mobility transport channel. Such devices can have a transconductance per unit channel width greater than that of state-of-the-art Si transistors. However, because of the limited current-carrying capacity of individual SWCNTs, many s-SWCNTs aligned side by side in a single device would be required in order to surpass the current drive of a Si device. Such precise positioning of SWCNTs is beyond the capability of current growth and assembly technology and presents a major technological hurdle for carbon nanotube-based electronic applications.